This invention relates generally to conveyors and other devices used to load heavy and/or awkward loads into trucks, and more particularly to conveyors that are used to store, sort, and load heavy and/or awkward objects such as mattresses into trucks, containers, or other confined areas.
Conveyors and the like, together with manpower have long been used to load trucks and move packages within a manufacturing facility. The use of many people to move objects within a plant or to load a truck with heavy and/or awkward objects is becoming less and less attractive as the cost of wages increase. In addition to the labor costs, there are costs associated with on the job injuries. These costs include both the costs of workers"" compensation insurance and the costs associated with loss of the injured individual""s labor for a period of time while the injury heals. During the period of time when a person is absent from work due to an injury, not only may the employer have to pay the absent worker, but the employer may also have to pay the wages of a replacement worker who may be unfamiliar with the employer""s operations.
Moving or loading of heavy and/or awkward items raises the risks substantially of the worker being injured. While the use of conventional methods can prevent many injuries, these tools are not effective for all types of cargo. For example, a large king size mattress can weigh as much as two hundred pounds and have dimensions exceeding six feet long, six feet wide, and fourteen inches high. Modern mattresses are both heavy and awkward for one person to carry and/or move by hand or with a dolly and are awkward to move from the machine that wraps the mattress in plastic to the truck.
Typically, a mattress is manufactured, wrapped, and shipped in the same day to ensure that the customer receives a xe2x80x9cfreshxe2x80x9d mattress. Thus, to save time and to ease the unloading process, mattresses are often manufactured in the order that they will be loaded in the truck or shipping container. Often, due to order changes or errors on the assembly line one or more mattresses may be manufactured out of the loading sequence. These out of sequence mattresses are typically piled in an area that is out of the way. When it is time to load one of the mattresses in the stack, the stack is disassembled, the selected mattress removed, and the other mattresses that are not yet required are re-stacked. This stacking, unstacking, sorting, and re-stacking takes time and reduce the number of mattresses that can be loaded in a day.
Therefore, a storage and sorting conveyor system that discharges to an extendable conveyor is needed that will enable a mattress manufacturer to collect mattresses quickly and easily from one or more wrappers, store, sort, and discharge mattresses, box springs, and/or other heavy and awkward packages to an extendable loading conveyor while minimizing the risk of injury to the worker. The extendable loading conveyor enables the mattresses to be loaded into trucks, containers, or other limited areas without the workers having to support the weight of the mattress.
The present invention has solved the package handling problems cited above and generally comprises a mattress storage and sorting conveyor that discharges to one or more extendable conveyors. The storage and sorting conveyor has a feed section that collects the mattress from one or more wrappers and inserts the mattress onto a circulating system which stores the mattresses until ready to be transferred elsewhere. Typically, this circulating system is located overhead to minimize the loss of floor space, although the circulating system may be located at any convenient location. A short length of the circulating system typically is repositioned to discharge a particular mattress to one or more conveyors that transport the mattress to a respective extendable conveyor. An operator at a control station selects which mattress to discharge from the circulating system. The conveyor system is controlled by a series of sensors, relays, and motor controllers to prevent or minimize the collisions between mattresses on the circulating system of the conveyor.
The extendable conveyor is a modification of existing extendable conveyors. The modifications enable the discharge end of the conveyor to move from a loading position near the top of the truck to a loading position near the bottom of the truck through out the length of the truck. This range of movement is greater than the range of movement that is typically employed in extendable conveyors and enables mattresses and other cargo to be loaded into a truck without the worker having to lift and/or catch the mattress or package. Additionally there may be provided dual control boxes at the discharge end of the conveyor to enable the conveyor to be controlled from either side depending on the worker""s preference and/or best location for observing and controlling the loading procedure.
An object of the present invention is to provide a mattress conveyor system for storing, sorting, and discharging mattresses to extendable conveyor that will permit a truck to be loaded with mattresses without a worker having to lift and/or catch a heavy mattress.
Additional objects, advantages and other novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.